1. Field of the Invention
The present invention relates to a photomultiplier tube for detecting incident light from outside.
2. Related Background Art
Conventionally, compact photomultiplier tubes by utilization of fine processing technology have been developed. For example, a flat surface-type photomultiplier tube which is arranged with a photocathode, dynodes and an anode on a translucent insulating substrate is known (refer to Patent Document 1 given below). The above-described structure makes it possible to detect weak light at a high degree of reliability and also downsize a device. Further, in the photomultiplier tube, there is known a structure in which in order to collect electrons more efficiently between dynodes constituted so as to be stacked in a plurality of stages, each of the dynodes is provided with an accelerating electrode part which projects to a through hole of a dynode which is an upper stage (refer to Patent Document 2 given below).    Patent Document 1: U.S. Pat. No. 5,264,693    Patent Document 2: Japanese Published Unexamined Patent Application No. Hei-8-17389